Dash Crack FAQ

Many Z cars, primarily the first-generation cars, suffer from cracked dashboards. This problem is not unique to Z cars, but just about any 20ish-year-old car with a dashboard made from a similar material is likely to have this problem. The information here was gleaned from the pages of the IZCC mailing list, and is summarized from reports from members, with a bit of commentary from me.

Uncracking a cracked dash

Buy a new dashboard and replace it

Have your cracked dash recovered

Replace it with a used, uncracked dash

Put a "cap" on it

Repair the cracks

Prevention
"What causes dashboards to crack?"
THE CONTROVERSY: PROTECTANTS

"301 Protectant" or maybe "303 Protectant"

How To Apply These Protectants

Uncracking a cracked dash
You just bought a cherry [insert favorite Z-car model here], beautiful in every respect, except the dashboard has cracks in it.

YOUR OPTIONS

1. Buy a new dashboard and replace it.
PROS: The finished product will look great. This is definitely the best solution for quality and originality.
CONS: (1) Effort. Removing and reinstalling a dashboard is a pretty big job. (2) Cost. A new dashboard might cost around $700 or even more by now. (3) Rarity. Finding a new dash may be a serious undertaking in itself. Needless to say, Nissan ain't makin' a whole lot of these any more.

2. Have your cracked dash recovered. PROS: (1) Quality. This is #2 on the list of quality and originality. In fact, it is possible, through superior products available today to those available in the '70s to get a higher-quality dash, but it is still less "original" than a genuine new part. (2) Availability. No need to search for a new part; it's already in your car! (3) Warranty: Some companies will even offer a lifetime warranty for their work! If it cracks, they will re-cover it for nothing. Also see a CON about this. CONS: (1) Effort. Still requires you to R&R the dashboard, which is a big job. (2) Cost. This can get to be pretty expensive. We've seen prices that vary, but, some even cost more than purchasing a new dash from the factory. Then again, the factory dashes may not be around that much longer. (3) Downtime. You must take the dash out of your car and deliver it to a shop to leave it for a few days or so to get this done. Your car is pretty much unusable for this time. (4) Originality: The newly covered dash will not be guaranteed to match the existing grain pattern of the original dash. Thus, it will probably look a little different. (5) Warranty: If it does crack, they will re-cover it for nothing, but, you will still have to R&R the dash yourself.

3. Replace it with a used, but uncracked dash.
PROS: (1) Cost. This may be a very cost-effective solution, particularly if you need other parts as well. I once came across a parts car with a beautiful dash, three engines, four transmissions, all other drivetrain parts, etc. for $700 locally [I should've bought it! -jk]. For someone in need of a dashboard, this would be a good choice. (2) Quality. You get an original part. Watch out, because it might be ready to crack!
CONS: (1) Effort. At a minimum, this requires a complete R&R of the dash, and if you go the route of the parts car you might have to do this twice. (2) Risk. This dash might be just about ready to crack! OOPS!

3. Put a "cap" on it.
PROS: (1) Cost. A full-face dash cap can be had for under $100. (2) Durability. The hard-plastic cap may be less likely to crack than the original dash. (3) Ease of installation. You don't have to remove the dash to install one of these!
CONS: (1) Quality. Let's be honest here. A capped dash looks pretty darned good, especially when you consider the cost, effort, and what the dash looked like before it was capped :-) However, it is not an original part. The cap is harder than the original dash and close inspection will reveal that it is a cap and not a "real" dash. (2) Risk. The appearance of a dash cap has a lot to do with the amount of care taken in installation. Done right, they look good, but a mistake may be hard to live with. Removing the cap may not be easy either. (3) Fit. Sources say Datsun may have used more than one mold for the early dashboards, and the cap may not fit properly. Unfortunately, the only way to know is to try. Odds are there won't be a problem, though.

4. Repair the cracks.
PROS: (1) Cost. This is even cheaper than a cap. If you do it yourself, you might be able to get the kit and lunch at Wendy's for under $20. Under $50 (?) for a pro job. (2) Effort. This is certainly not as much trouble as R&R the dash.
CONS: (1) Quality. This is a big maybe. Professionally done repairs can range from perfect to downright awful. (2) Durability. Odds are, the dash will crack again pretty soon (like a few years) in the same spot.
5. Live with it.
DREAM ON, GARCON!!

Prevention

Unfortunately, much of the discussion of how to prevent a dashboard from cracking has little real, scientific basis that I could find on the Z car list. There is a bit of theory, and a wealth of owner's experiences available there, but what the difinitive "right answer" is may not be possible to evaluate given the data available from the mailing list archives. Here, I will attempt to present all of the arguments and summarize the pros and cons of each solution. You will have to evaluate what you think is best on your own.

Before we get into how to prevent your uncracked dash from becoming a cracked dash, it makes sense to get into exactly what makes a dashboard crack. While I'm no expert, there are some IZCC members who either are experts or were thoughtful enough to colsult experts on our behalf, and I will use their descriptions as fact here.

"What causes dashboards to crack?"

Tom, friend of IZCC member Carl Beck, engineer/scientist in the Aerospace industry says:

"1. Ultra Violet light, depending on its wavelength, is in fact ionizing radiation. It can dissassociate and even ionize molecules.
"2. If the damage to the dash parts is "cracks" it is probably from heat, (which couses outgassing or drying). If it is "powdering of the surface" it may be >from UV light. Even material with a very high absorption coefficient transmits a small amount of UV light. A very bright UV source (the sun) over a very long time can cause damage through a car window.
"3. The UV from the sun is sufficiently intense and energetic to cause blindness in a fairly short time (staring directly into the sun for 10 minutes). The sunglasses are to protect the retina from UV light."

So we can conclude that the cause of the dashboard cracking is [drum roll please]... THE SUN! So for an uncracked dash to stay that way, it must be protected from the sun. The other method is to undo the damage that the sun does. Since there is really no way to completely protect your dash from the sun (except, maybe to keep it in the garage during the day and only drive at night :-), then this makes sense. There is also mention on the list that dashboard cracking may be related to high temperatures inside the cabin of the car, and also may be related to rapid and/or extreme changes in interior temperature.

Cover the dash when it is in the sun. This is simple and makes lots of sense. The easy and cheap way to do this is with a towel or a sheet [I use a pair of hand-towels -jk]. Custom-fit covers are available commercially if you are inclined to utilize a prettier solution, but for about the same money you can get a car cover, which is probably the best solution [plus, it will protect the paint, seats, carpets, and can discourage thieves from stealing your radio when used in conjunction with an alarm -jk]. To reduce interior temperatures, tinted windows may help but ultimately a car cover is the best bet.

THE CONTROVERSY: PROTECTANTS

"Protectants" refers to substances that you may apply to the dashboard to prevent it from cracking by undoing the effects of the sun (or, perhaps, by blocking UV, etc.). Most of these products tend to restore oils that are lost due to "outgassing" or "drying". Some of the items listed here are not commercial car-care or vinyl-care products, but have been reported to have the effect of keeping the dashboard looking good when applied in similar fashion to those designed for vinyl.

This is a controversial topic, primarily because there are a lot of options and very little objective information available.

Armor-All
Probably the most widely-known and widely-used vinyl "protectant" product, Armor-All dominates the market and has been the topic of much heated debate. Opponents to Armor-All have claimed that Armor-All causes the dashboard to dry out and crack more quickly than it would have had it been left untreated due to it bringing oils in the vinyl to the top. Many IZCC members have backed up this claim with experience, mostly having to do with applying Armor-All to dashboards that, although uncracked, were old and may not have been treated with Armor-All in the past. Reports are that after applying Armor-All to an uncracked dash it cracked in a very short time (weeks). In Armor-All's defense, one member is the original owner of a 23-year-old Z and has faithfully used Armor-All and nothing else, and there are no cracks in the dash [I should point out that this particular IZCC member excercises a great deal of care and feeding of his cars -jk]. There are also reports of an ex-Armor-All employee who alleges that the company intentionally sold the product knowing full well that it would have adverse affects on vinyl parts that it is used on. By far, the overwhelming opinion of IZCC members seems to be that it is not the best choice to keep your dash looking good long-term.

This came off the archives, from a LA Times article:

"Headline: 'Luster Is Off of Armor All Protectant Ad'

"Content (summarized):

"1. Armor All's ad campaign comparing AA to the 'other product' (Son of a Gun, but not identified by name) was deemed to be misleading by the Nat'l Advertisi Dvsn of the Better Biz Bureau.

"2. AA has about 65% of the market for rubber/vinyl protectants.

"3. AA has been criticized by 'some' independent car cleaning & polishing businesses, according to whom AA can harm vinyl dashboards and car tops exposed to heavy sun. However, these reports have never been validated.

"4. Earlier this year, a former AA research manager, in the context of a wrongful termination suit against AA, claimed that the co. had covered up research that indicated AA caused tires & air bag covers to weaken & crack. AA denies the allegations. The suit is pending."

You should draw your own conclusions.

Nu-Vinyl
There is brief mention of this product on the list, stating that it is non-greasy and easy to apply. No other information is available on the list.

"Vaseline"
"Vaseline" (petroleum jelly) seems to be the champion of the protectant wars. It is inexpensive and I could find no reports of adverse effects attributable to using petroleum jelly. There are numerous reports from IZCC members personal experience that petroleum jelly works best, and even some second-hand testimonial from professional dashboard-recoverers and other experts.

Sun Screen
The idea here is that if sun screen can block UV radiation when applied to your skin, then it may also have similar effects on with a dashboard. Caveats exist, however, mostly involving residue left on the dash after the sunscreen dries, etc. Using sun screen to block UV does not restore the oils in the vinyl, so it is generally advised to apply petroleum jelly or some other protectant after applying the sun screen,

"301 Protectant" or maybe "303 Protectant"
Mentioned briefly, two different names may actually be the same product (??), in what sounded like a commercial, "301/303 Protectant" claims to not have the problems associated with Armor-All.

How to apply these protectants

2. Apply the protectant with a soft, lint-free cloth. Be sure to cover all vinyl surfaces.

3. Wipe off any excess with another cloth. "Buffing" the dash may make it shinier, if that is a desirable effect for you.

Dash Crack FAQ by Josh Karnes (joshk@tanisys.com). Last updated 9/18/95. Please email me with any additional information that I should have here, or suggestions, etc.

Dash Crack FAQ

Contents

Prevention

"What causes dashboards to crack?"

THE CONTROVERSY: PROTECTANTS

How to apply these protectants